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Porphyrins,phthalocyanines,and related covalent-organic frameworks in the photochemical and electrochemical water splitting:A review

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Particuology 2024年第7期90卷 236-265页

作者： Oxana v.Kharissova Yolanda Peña Méndez boris I.Kharisov Aleksandr LNikolaev Edith Luévano-Hipólito Lucy T.González Universidad Autónoma de Nuevo León Ave.Universidad s/nSan Nicolás de los GarzaNuevo León66455Mexico Department of Chemistry Moscow State UniversityVorobievy HillsMoscowRussia CONACYT-Universidad Autónoma de Nuevo León Facultad de Ingeniería Civil-Departamento de Ecomateriales y EnergíaCd.UniversitariaC.P.66455San Nicolás de los GarzaNLMexico Tecnologico de Monterrey Escuela de Ingeniería y CienciasMonterreyNuevo León 64890Mexico Tecnologico de Monterrey Centro del AguaMonterreyNuevo León 64890Mexico

In this review,the possibilities of photochemical and electrochemical water splitting(WS)using porphyrins,phthalocyanines,related macrocycles,and their metal complexes are *** efforts are being carried out in order to develop novel and cheap methods for water decomposition to generate inexhaustible greener energy sources(molecular hydrogen)instead of oil and *** processes of WS in heterogeneous and homogeneous media require novel photo-and electrocatalysts,in particular those on macrocycle basis.A high WS efficiency has been observed for porphyrins and phthalocyanines,showing their suitability both for HER and OER processes are available using these relative compounds for WS *** can be used in photocatalytic and electrocatalytic WS processes both in their free forms or as metal porphyrins/porphyrinates,mainly loaded on various inorganic materials,such as Au NPs,C_(3)N_(4),GaP,KTaO_(3),GaP,and so on,as part of porphyrin-containing polymers or on electrode surface as modifying coatings,being sometimes better than commercial catalysts,such as Pt/*** H2 evolution can be considerably depended on the shape of porphyrin particles;in particular,porphyrin nanowires can yield up to 20 times more H2 than its *** certain cases,both HER and OER can be driven in the same electrolyte using metal *** capacity of metal porphyrins to generate ROS(in particular,singlet oxygen 1O_(2))under ultrasonic treatment is known and can be successfully used for H_(2)O_(2) and O_(2) *** can be used in similar processes in free form or as composites with inorganic or organic counterparts,being immobilized on nanocarbons,metal oxides and salts,or simply dissolved in water acting in a homogeneous *** additional use of ultrasound can lead to better results due to the synergistic effect of the sonochemical treatment and ***-organic frameworks are also applied for WS purposes and are mainly based

关键词： Porphyrins Phthalocyanines COFs Water splitting Photocatalysis Electrocatalysis

Hydroxyapatite composites with carbon allotropes:Preparation,properties,and applications

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Particuology 2024年第5期88卷 239-265页

作者： boris I.Kharisov Oxana v.Kharissova Lucy T.González Yolanda Peña Méndez Igor E.Uflyand Idalia Gómez de la Fuente Universidad Autónoma de Nuevo León Ave.UniversidadCiudad UniversitariaSan Nicolás de los GarzaNuevo León 66455Mexico Tecnologico de Monterrey Escuela de Ingeniería y CienciasMonterreyNuevo Leon 64890Mexico Department of Chemistry Southern Federal UniversityRostov-on-DonRussia

Hydroxyapatite(HA)and its composites with inorganic additives,dopants,and polymers is a rapidly developing branch in the materials *** particular,carbon allotropes are widely used in these composites being widely applied for medical *** a gap of insufficient generalization of recent achievements in the field of the HA/Carbon composites,in this review we present the state of the art of the field of HA composites and hybrids with classic carbon allotropes and *** composites are known for carbon nanotubes,nanofibers,graphene and its oxidized forms,as well as,in a lesser grade,for graphite,fullerenes,nanodiamonds,carbon nanofoams,*** composites can be fabricated by a variety of classic and less-common methods,such as co-precipitation(with or without ultrasonic treatment),CvD,hot isostatic pressing,hydrothermal,spark plasma sintering,biomimetic mineralization,thermal and plasma spray,electrochemical and electrophoretic deposition,self-assembling,3D printing,electrospinning,and lyophilisation,among *** of various synthesis techniques can be also carried out for composite *** or synthetic HA can be used as it is for further interaction with carbon allotropes or it can be first prepared and then reacted with carbon counterpart;similarly,carbon allotropes can be introduced into the interaction with HA directly or they can be first synthesized,in particular from *** biocompatible composites can be produced in the form of coatings,powders,and scaffolds and can additionally contain quantitative amounts of third phases,frequently natural or synthetic *** these composites,especially with O-containing functionalizing groups,HA disadvantages could be considerably decreased with simultaneous enhancement of mechanical properties,becoming similar to human bone,chemical stability and biocompatibility,as well as possessing antibacterial ***→G reduction and higher HA decoration were obs

关键词： Hydroxyapatite Carbon nanotubes Graphene Quantum dots Fullerenes Nanodiamonds

Non-coding RNAs in exercise immunology:A systematic review

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Journal of Sport and Health Science 2024年第3期13卷 311-338,I0002页

作者： Mona Kotewitsch Melina Heimer boris Schmitz Frank C.Mooren Department of Rehabilitation Sciences Faculty of HealthUniversity of Witten/HerdeckeWitten 58455Germany DRv Clinic Konigsfeld Center for Medical RehabilitationEnnepetal 58256Germany

Regular physical exercise has been recognized as a potent modulator of immune function,with its effects including enhanced immune surveillance,reduced inflammation,and improved overall *** strong evidence exists that physical exercise affects the specific expression and activity of non-coding RNAs(ncRNAs)also involved in immune system regulation,heterogeneity in individual study designs and analyzed exercise protocols exists,and a condensed list of functional,exercise-dependent ncRNAs with known targets in the immune system is missing from the literature.A systematic review and qualitative analysis was used to identify and categorize ncRNAs participating in immune modulation by physical *** combined approaches were used:(a)a systematic literature search for“ncRNA and exercise immunology”,(b)and a database search for microRNAs(miRNAs)(miRTarBase and DIANA-Tarbase v8)aligned with known target genes in the immune system based on the Reactome database,combined with a systematic literature search for“ncRNA and exercise”.Literature searches were based on PubMed,Web of Science,and SPORTDiscus;and miRNA databases were filtered for targets validated by in vitro experimental *** were eligible if they reported on exercise-based interventions in healthy *** duplicate removal,95 studies were included reporting on 164 miRNAs,which were used for the qualitative *** studies reporting on long-noncoding RNAs(lncRNAs)or circular RNAs were also *** were analyzed using ordering tables that included exercise modality(endurance/resistance exercise),acute or chronic interventions,as well as the consistency in reported change between *** criteria were defined as“validated”with 100%of≥3 independent studies showing identical direction of regulation,“plausible”(≥80%),or“suggestive”(≥70%).For resistance exercise,upregulation of miR-206 was validated while downregulation of miR-133a appeared *** endurance exer

关键词： Immune system Inflammation MicroRNA ncRNA Physical exercise

How to fill the biodiversity data gap:Is it better to invest in fieldwork or curation?

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Plant Diversity 2024年第1期46卷 39-48页

作者： Carlos A.vargas Marius Bottin Tiina Sarkinen James E.Richardson Marcela Celis boris villanueva Adriana Sanchez Programa de Biología Facultad de Ciencias NaturalesUniversidad del RosarioBogotaD.C.Colombia Subdireccion Científica Jardín Botanico de Bogota“Jose Celestino Mutis”BogotaD.C.Colombia Independent Researcher BogotaD.C.Colombia Tropical Diversity Section Royal Botanic Garden EdinburghUK School of Biological Earth and Environmental SciencesUniversity College CorkCorkIreland Departamento de Química y Biología Universidad del NorteKm.5 Vía Puerto ColombiaArea Metropolitana de Barranquilla 081007Colombia

Data gaps and biases are two important issues that affect the quality of biodiversity information and downstream *** how best to fill existing gaps and account for biases is necessary to improve our current information most *** current main approaches for obtaining and improving data include(1)curation of biological collections,and(2)***,the comparative effectiveness of these approaches in improving biodiversity data remains little *** used the Flora de Bogota project to study the magnitude of change in species richness,spatial coverage,and sample coverage of plant records based on curation versus *** process of curation resulted in a decrease in species richness(synonym and error removal),but it significantly increased the number of records per *** contributed to a slight increase in species richness,via accumulation of new ***,curation led to increases in spatial coverage,species observed by locality,the number of plant records by species,and localities by species compared to ***,curationwas more efficient in producing new information compared to fieldwork,mainly because of the large number of records available in *** recommend intensive curatorial work as the first step in increasing biodiversity data quality and quantity,to identify bias and gaps at the regional scale that can then be targeted with *** stepwise strategy would enable fieldwork to be planned more costeffectively given the limited resources for biodiversity exploration and characterization.

关键词： Colombia Flora de Bogota Sample coverage Species richness Tropical Andes

Olefin Polymerization Behavior of Titanium(Iv) Complexes with Fluorinated and Non-fluorinated Aliphatic Phenoxyimine Ligands

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Chinese Journal of Polymer Science 2024年第1期42卷 52-62,I0007页

作者： vladislav A.Tuskaev Kasim F.Magomedov Svetlana Ch.Gagieva Dmitry A.Kurmaev Yulia v.Nelyubina Evgenii K.Golubev Maria D.Evseeva viktor G.vasil'ev Galina G.Nikiforova Mikhail I.Buzin vyacheslav S.Bogdanov boris M.Bulychev Department of Chemistry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation Enikolopov Institute of Synthetic Polymer Materials Russian Academy of SciencesMoscow 117393Russian Federation

A series of Ti(Ⅳ) dichloride and dialkoxide com plexes with phenoxyimine ligands containing fluorinated and nonfluorinated aliphatic imine fragments have been *** molecular structures of complexes 1 and 4 were established by single-crystal X-ray diffraction *** complexes adopt a distorted octahedral coordination structure around the titanium atom and two oxygen atoms are situated in trans position while two nitrogen atoms and two outgoing ligands(Cl or iPrO) are situated in cis *** of activators(MMAO-12 and combinations Et_nAICl_(3-n)+Bu_(2)Mg) and outgoing ligand(Cl or iPrO) nature on the catalytic activity and properties of the resulting polymers was *** Ti complexes,despite the nature of the outgoing ligands(Cl or iPrO) in the presence of Al/Mg activators,was found to display a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a viscosity average molecular weight(M_v) value in the range 1.1×10~6-7.1×10~6 Dalton(Da).The resulting UHMWPE can be processed by a solventless method into high-strength and high-modulus oriented *** rheological characteristics of a polymer melt have been *** absence of a cross-over point did not allow to compare the values of the molecular weight distribution of polymers obtained on fluorinated and non-fluorinated pre-catalysts,however,the estimation of the entanglement density is in good agreement with the mechanical characteristics of oriented film *** activation with methylalumoxane,the activity of the com plexes decreased very significantly;however,a polymer with a molecular weight of about 12 million Da was *** the process of ethylene/octene-1 copolymerization,fluorine-containing precatalysts showed a clear advantage over non-fluorinated analogues both in activity and in comonomer content.

关键词： FI catalysts Titanium(Iv) (Co)polymerization Al/Mg co-catalyst Ultra-high molecular weight polyethylene

Mechanism of the Initial Stage of Thermal Decomposition of Nitroguanidine

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火炸药学报 2023年第1期46卷 31-40页

作者： boris E.Krisyuk Danila A.Markin Timofey M.Sypko viktor v.Zakharov Nikita v.Chukanov boris L.Korsunskiy Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry Russian Academy of Sciences142432prosp.Academician Semenov1ChernogolovkaMoscow RegionRussia Plekhanov Russian University of Economics Department of Chemistry and Physics36 Stremyanny laneMoscow 117997Russia Lomonosov Moscow State University Faculty of Fundamental Physical and Chemical engineeringGSP-11 Leninskie Goryp.51Moscow 119991Russia N.N.Semenov Federal Research Center for Chemical Physics Russian Academy of Science 4 Kosygina StreetBuilding 1Moscow 119991Russia

A theoretical and experimental study of the thermal decomposition of nitroguanidine(NQ) has been carried out. various thermolysis channels were studied by quantum chemistry methods at the CCSD(or DLPNO-CCSD) level using the aug-cc-pvDZ basis set. It is shown that the lowest activation enthalpies(170-180kJ/mol) are characteristic of the reactions of NO2abstraction from the initial NQ and the reaction channel with the transfer of oxygen from the nitro group to carbon in the limiting stage. Additionally, the thermolysis of NQ was studied experimentally in a nonisothermal mode with heating rates from 1 to 10K/min. In these experiments, the weight loss of the sample, thermal effects, and mass spectra of the products were recorded. An analysis of the experimental data confirmed the results of a theoretical study of the mechanism of thermal decomposition of NQ. The main thermolysis products are N2O, HNCO, NH3, and NO2, which fully corresponds to quantum chemical calculations.

关键词： primary thermolysis steps quantum-chemical calculation mass spectrometry DSC TG

Spontaneous Twist and Intrinsic Instabilities of Pristine Graphene Nanoribbons

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Nano Research 2009年第2期2卷 161-166页

作者： Ksenia v.Bets boris I.Yakobson Department of Mechanical Engineering&Materials Science Department of Chemistryand The Richard E.Smalley Institute for Nanoscale Science and TechnologyRice UniversityHoustonTexas 77005USA

In pristine graphene ribbons,disruption of the aromatic bond network results in depopulation of covalent orbitals and tends to elongate the edge,with an effective force of fe~2 ev/Å(larger for armchair edges than for zigzag edges,according to calculations).This force can have quite striking macroscopic manifestations in the case of narrow ribbons,as it favors their spontaneous twisting,resulting in the parallel edges forming a double helix,resembling DNA,with a pitchλt of about 1520 lattice *** atomistic simulations,we investigate how the torsionτ~1/λt decreases with the width of the ribbon,and observe its bifurcation:the twist of wider ribbons abruptly vanishes and instead the corrugation localizes near the *** length-scale(λe)of the emerging sinusoidal“frill”at the edge is fully determined by the intrinsic parameters of graphene,namely its bending stiffness D=1.5 ev and the edge force fe withλe~D/*** reveals other warping configurations and suggests their sensitivity to the chemical passivation of the edges,leading to possible applications in sensors.

关键词： Graphene nanoribbons mechanics twist

Post-Late Paleozoic Collisional Framework of Southern Great Altai

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Acta Geologica Sinica(English Edition) 2012年第5期86卷 1093-1104页

作者： boris M. CHIKOv Sergei v. ZINOvIEv Еugene v. DEYEv Institute of Geology Siberian Branch of Russian Academy of Sciences Novosibirsk 630090 Russia

We outline the post-Late Paleozoic （latest Permian to Cenozoic） collisional framework of the southern Great Altai （Central Asia） produced by the convergence between the Tuva-Mongolia and Junggar continental terranes （microplates）. The collisional structures in the region classified on the basis of their geometry and deformation style, dynamic metamorphism, and compositions of tectonites are of three main types：（1） mosaic terranes made up of large weakly deformed Paleozoic blocks separated by younger shear zones; （2） contractional deformation systems involving structures formed in post-Late Paleozoic time, parallel faults oriented along collisional deformation systems, and relict lenses of Paleozoic orogenic complexes; and （3） isolated zones of dynamic metamorphism composed mostly of collisional tectonites different in composition and alteration grade.

关键词： continental collision post-Late Paleozoic events tectonic framework dynamic metamorphism Altai Central Asia

Synthesis, X-ray structure and luminescent properties of Sm^(3+) ternary complex with novel heterocyclic β-diketone and 1,10-phenanthroline (Phen)

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Journal of Rare Earths 2011年第8期29卷 719-722页

作者： Ilya v. Taydakov boris E. Zaitsev Sergey S. Krasnoselskiy Zoya A. Starikova G. S. Petrov Institute of Plastics JSC Perovskiy proezd 35 Moscow 111024 Russian Federation People's Friendship University of Russia A. N. Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences

A new neutral ternary samarium complex Sm（Phen）HL3 in which Phen is 1,10-phenanthroline and HL is （1,3-bis（1,3-dimethyl-1H-pyrazol-4-yl）-1,3-propanedione） was synthesized. Molecular structure of this complex was determined by X-ray diffraction. Under Uv-light this complex is demonstrated bright red luminescence （λmax=647 nm）, which was corresponding to the electric dipole 4G5/2→6H9/2 transition in Sm3＋ ion. Uv-absorption, excitation and emission spectra of the title compound were investigated.

关键词： samarium pyrazole β-diketone crystal structure photoluminescence rare earths